diff --git a/src/graphics/graphics.c b/src/graphics/graphics.c
index 6be89ca..d7a305c 100644
--- a/src/graphics/graphics.c
+++ b/src/graphics/graphics.c
@@ -616,6 +616,11 @@ static inline int erase_arrow (int arrows_nb, int address, int site, int x, int
     arrows_ptr[address].y = arrows_ptr[arrows_nb].y;
     arrows_ptr[address].z = arrows_ptr[arrows_nb].z;
 
+    for (int i = 0 + address; i < 6 + address; i++)
+    buffer_vertex_origin [(long) buffer_vertex_0_arrow + i] = buffer_vertex_origin[(long) buffer_vertex_size - 6 + i];
+
+    for (int j = 0 + address; j < 4 + address; j++)
+    buffer_lines_origin [(long) buffer_lines_0_arrow + j] = buffer_lines_origin[(long) buffer_lines_size - 4 + j];
 
     if (arrows_nb > 0) {
 
@@ -623,12 +628,17 @@ static inline int erase_arrow (int arrows_nb, int address, int site, int x, int
         if (new_arrows_list_ptr) arrows_ptr = new_arrows_list_ptr;
         else                     perror("In erase arrow, can't re_allocate for arrow list.\n");
 
-        printf("buffer_vertex_0_arrow = %d   arrows_nb * 3 = %d     <<<<\n", buffer_vertex_0_arrow, arrows_nb * 3);
+        /* long unit = 24 * 3 * sizeof(GLfloat);  //  4 * 3 * 4 = 48   sizeof(GLfloat) = 3 * 8 bits */
+        /* printf(" - erase_arrow() invoked with address = %d    buffer_vertex_size - buffer_vertex_0_arrow = %d  (for %d arrows)\n",\ */
+        /*        address, (long) buffer_vertex_size - buffer_vertex_0_arrow, arrows_nb + 1); */
+        /* for (int i = 24; i < 36; i ++) printf(" %5.2f", buffer_vertex_origin[i]); printf("\n"); */
+
+        if (0) printf("buffer_vertex_0_arrow = %d   arrows_nb * 3 = %d     <<<<\n", buffer_vertex_0_arrow, arrows_nb * 3);
         void *new_arrows_vertex_ptr = g_realloc(buffer_vertex_origin, buffer_vertex_0_arrow + 9 * 3 * sizeof(GLfloat));
         if (new_arrows_vertex_ptr) buffer_vertex_origin = new_arrows_vertex_ptr;
         else                       perror("In erase arrow, can't re_allocate for arrow vertex buffer.\n");
 
-        printf("buffer_lines_0_arrow = %d   arrows_nb * 2 = %d     <<<<\n", buffer_lines_0_arrow, arrows_nb * 2);
+        if (0) printf("buffer_lines_0_arrow = %d   arrows_nb * 2 = %d     <<<<\n", buffer_lines_0_arrow, arrows_nb * 2);
         void *new_arrows_lines_ptr = g_realloc(buffer_lines_origin, buffer_lines_0_arrow + 9 * 2 * sizeof(GLfloat));
         if (new_arrows_lines_ptr) buffer_lines_origin = new_arrows_lines_ptr;
         else                       perror("In erase arrow, can't re_allocate for arrow lines buffer.\n");
@@ -669,7 +679,7 @@ static inline int set_arrow (struct arrow_t *arrows_ptr, int arrows_nb,
         }
     }
 }
-    if (requested_weight == 0) printf("[%d]set_arrow() invoked with requested weight = %2d\n", arrows_nb, requested_weight);
+    if (requested_weight == 0) printf(" - set_arrow()   invoked with requested weight = %2d\n", requested_weight);
 
     if (TEST) show_user_action(arrows_ptr, arrows_nb, address, requested_weight, current_weight, site, x, y, z);